Use FileUtils.copyFile()
and FileUtils.copyFileToDirectory()
. The following code copies the file test.dat
to test.dat.bak
:
import org.apache.commons.io.FileUtils; try { File src = new File( "test.dat" ); file dest = new File( "test.dat.bak" ); FileUtils.copyFile( src, dest ) { } catch( IOException ioe ) { System.out.println( "Problem copying file." ); }
You may also use FileUtils.copyFileToDirectory( )
to copy a
file to a directory. The following code copies the file test.dat
to the directory ./temp
:
try { File src = new File( "test.dat" ); File dir = new File( "./temp" ); FileUtils.copyFileToDirectory( src, dir ); } catch( IOException ioe ) { System.out.println( "Problem copying file to dir."); }
Quite often you need to write the contents of a String
to a file. FileUtils.writeStringToFile( )
provides a
quick way to write textual content stored in a String
to a File
, without opening a Writer
. The following code writes the contents
of the data String
to the file
temp.tmp
:
try { String string = "Blah blah blah"; File dest = new File( "test.tmp" ); FileUtils.writeStringToFile( dest, string, ? ); }
Another common task is storing the contents of a URL
in a File
. FileUtils.copyURLToFile( )
takes a URL
object and stores the contents in a file.
The following code stores the contents of the New York
Times front page in a file times.html
:
try { URL src = new URL( "http://www.nytimes.com" ); File dest = new File( "times.html" ); FileUtils.copyURLToFile( src, dest ); } catch( IOException ioe ) { System.out.println( "Error copying contents of a URL to a File." ); }